1. Field of the Invention
The invention relates to an instrument panel such as used for navigational purposes, and more particularly toward an improved technique for lighting indicia in a vehicle instrument cluster to create an aesthetic dimensional effect.
2. Related Art
The instrument cluster and gauges in a typical motor vehicle must be clearly visible by the operator during all ambient lighting conditions. For example, a driver must be able to clearly read the gauges during bright sunlight as well as during nighttime driving. For this reason, the various colors applied to different components and the lighting or illumination of those components must be adaptable to different conditions. Various illumination techniques, such as incandescent lighting, florescent lighting, and LED lighting have been used to accomplish both daytime and nighttime gauge illumination.
In addition to the functional requirements of visibility placed upon the instrumentation, this area of a vehicle has become a favored target of designers and stylists who attempt to create dazzling and visually impressive presentations. Such impressive stylizations often become a determining factor in a consumer's buying decision.
One such stylistic feature has included the use of phosphor coated indicia within the housing of the instrument cluster which can be selectively energized by an ultraviolet (UV) light source. The phosphor coated indicia presents a different color to an observer when irradiated, than it does in a non-energized state. The resulting instrument cluster can thereby provide an aesthetically appealing display when energized. Examples of prior art instrument panels including phosphor or other UV sensitive indicia may be found in U.S. Pat. No. 5,920,150 to Crary, et al issued Jul. 6, 1999. Other examples may be found in US Publication No. 2002/0186556 to Wojnarowski, published Dec. 12, 2002 and US Publication No. 2004/0189483 to Stringfellow, published Sep. 30, 2004. In all of these examples, UV-irradiated indicia may be located within the confines of an instrument panel housing and selectively energized by the UV light source to develop aesthetically interesting effects.
All of these prior art examples emphasize the attention that is given to the instrument cluster and the general appeal of various lighting effects to generate consumer interest. Accordingly, these prior art underscore the need for functional instrument panels which are both clearly visible to a driver during all lighting conditions and also present unique and stylistically impressive visual displays.